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Since a comprehensive fish survey in 1968, four impoundments have been constructed in the Bear Creek (Tennessee River drainage) watershed in Alabama (Wall 1968). Data from this original study were compared to a recent survey in order to determine if any changes in fish species composition had occurred during the approximately 30 year time period. A comparison of similarity for 44 collections showed low similarity between the two surveys for a large percentage of sites visited (86% for Jaccard's Similarity and 62% for Morisita Similarity). Sites with low similarity between survey dates were typically associated with impoundments. Most species missing in the recent survey include species considered sensitive, such as cyprinids and percids. Species that have increased since 1968 include centrarchids, a group typically tolerant of impoundment and environmental change. Virtually all fish species composition differences indicate a less pristine fish assemblage in the more contemporary survey, suggesting that recent factors have had a negative effect on the fish assemblage of Bear Creek. [ABSTRACT FROM AUTHOR]